Morphological diversity assessment in date palm (Phoenix dectylifera L.) germplasms grown under hot arid region of India

Abstract Background Date palm (Phoenix dactylifera L.) is a vital fruit crop cultivated in hot, arid regions due to its economic, nutritional, and ecological significance. Understanding the morphological diversity among different genotypes is crucial for breeding, conservation, and improving yield potential. The current study aimed to assess the phenotypic diversity of 37 date palm genotypes from 27 accessions grown in India's arid climate, focusing on 26 morphological traits. Results The study employed statistical analyses such as ANOVA, correlation analysis, and principal component analysis (PCA) to evaluate trait variability and their contributions to yield improvement. Key traits like leaf length (CH1), leaflet length (CH2), bunch length (CH9), bunch weight (CH15), fruit weight (CH16), and pulp weight (CH20) exhibited significant genetic variation. Correlation analysis revealed strong positive associations between bunch weight (CH15) and key yield components, including yield per plant (CH26), number of bunches per plant (CH7), and fruit traits like weight (CH16), width (CH18), and length (CH17). Additionally, negative correlations were observed, such as stone weight (CH19) with the pulp-to-stone ratio (CH21) and total soluble solids (CH25), highlighting trade-offs in fruit composition. The impact of both genetic and environmental factors on trait expression was demonstrated by PCA, which further separated genotypes such as Medjool (MDL) and Tayer (TYR) based on fruit weight and yield, respectively. Principal component analysis (PCA) demonstrated that PC1, PC2, and PC3 accounted for a significant portion of the total variation, with leaf length, bunch length, fruit weight, and pulp weight being key contributors. Additionally, cluster analysis grouped genotypes into two major clusters, identifying genetically similar accessions such as Gizej and Sakaloti, as well as Binet-A-Isha and Tayer, which could serve as promising breeding material. Conclusion These findings emphasize the rich morphological diversity within date palm accessions and highlight the potential of key morphological traits in breeding programs aimed at enhancing fruit quality and yield stability under hot-arid conditions.